A resonant circuit is an electrical circuit in which resonance occurs at a particular frequency.
Resonance Condition: \[ \omega L = \frac{1}{\omega C} \]
Resonant Frequency: \[ f = \frac{1}{2\pi \sqrt{LC}} \] \[ \boxed{f = \frac{1}{2\pi \sqrt{LC}}} \]

What is the first law of Kirchhoff of the electrical circuit? Find out the potential difference between the ends of 2 \(\Omega\) resistor with the help of Kirchhoff's law. See the figure: